The present invention relates to a centrifuge rotor cover assembly. More particularly, the present invention relates to a method and apparatus for attaching a cover to a centrifuge assembly.
Centrifuges typically include a housing with a centrifuge chamber, a rotor and drive spindle that supports samples to be centrifuged, a rotor cover and a chamber door. The centrifuge chamber within which the rotor rotates is covered by the chamber door during centrifugation to protect the centrifuge operator from the spinning parts in the chamber. The chamber door also provides containment should material be projected from the rotor during rotor rotation. The rotor cover encloses the samples inside the rotor and provides an aerodynamic smooth surface to reduce air friction during operation. The rotor cover is moveable between an open and closed position. The open position accommodates access to the rotor and while in the closed position the cover encases the rotor.
During normal centrifuge operation, a liquid sample is disposed and sealed within a receptacle, usually a centrifuge sample tube, and the tube is placed within holes located on the rotor. Thereafter, the rotor cover is placed in the closed position, covering the rotor and readying the centrifuge for operation. Occasionally the centrifuge tubes may leak. This leakage can result from improper sealing of the tube, using a tube not rated for the rotor operating speed, and/or using a tube composed from material that is chemically incompatible with the sample. As a result of the aforementioned leakage, the centrifuge components may become contaminated with the samples.
In existing centrifuges, the rotor cover is designed as a separate piece or unit from the rotor and requires manual attachment and detachment for each use. One current method for attachment includes utilizing a captive nut on the rotor cover that is screwed onto a threaded post located on the center of the drive spindle of the rotor. Another current method includes utilizing clamping studs, each having threaded members, wherein the studs are inserted into receiving portions on the rotor and drive spindle and rotated several times to secure the cover to the rotor and the rotor to the drive spindle.
Current rotors have threaded clamping studs; one is used to attach the cover to the rotor and the other is used to attach the rotor to the drive spindle. These studs are oriented in series such that the rotor to drive spindle clamping stud must be disengaged first and then the cover to rotor clamping stud must be disengaged. The cover can then be removed to gain sample access. A problem that sometimes occurs in the operation of these covers is that they are time consuming to operate because many employ multiple threaded parts that each are required to be rotated multiple times to attach the cover to the rotor and the rotor to the drive spindle. Each attachment piece must be manipulated by the centrifuge operator in order to ensure the cover is securely attached to the rotor prior to centrifuge operation and subsequently disengaged after centrifuge use, preventing the centrifuge operator from gaining access to his or her samples quickly and efficiently.
In view of the foregoing, it is desirable to provide a rotor cover for effectuating quick, efficient access to the rotor of a centrifuge. It is also desirable to provide secure attachment and sealing of a rotor cover and detachment of a centrifuge rotor cover, employing a minimum number of steps and components.
The foregoing needs are met, at least in part, by the present invention where, in one embodiment, an attachment and release apparatus for use with a centrifuge rotor cover is provided having a housing with a first passage, and a plunger having an annular groove that is slidably disposed within the housing. A first biasing element is disposed within the housing. The apparatus also has an adapter having a first detent, that is removeably connected to the housing. In addition, a first moveable element is disposed within the first passage of the housing, and it is moveable between an attached position and a release position. The first moveable element is in the attached position when it is at least partially in the first detent of the adapter and contacts the plunger.
In accordance with another embodiment of the present invention, an attachment and release apparatus for use with a centrifuge rotor cover is provided having a housing wherein the housing has a first passage and a retaining ring and a cover disposed around the housing. The apparatus additionally has an adapter that is removeably connected to the housing wherein the adapter has a first detent along with a receiver portion. The apparatus further includes a plunger having a first and second contact surface that is slidably disposed within the housing. In addition, the apparatus also includes a slider member disposed around the plunger that slidably engages both the plunger and the housing. The slider member has an annular groove. The apparatus also includes a first biasing member located between the slider and the plunger and a first moveable element. The first moveable element is disposed within the first passage of the housing and it is moveable between an attached position and a released position. The first biasing member exerts a force in a first direction, displacing the slider member in the first direction and aligning the first passage with the slider annular groove. The first moveable element moves between the first passage and the slider annular groove, when the first moveable element is in the released position.
In yet another embodiment of the present invention, an attachment and release apparatus for use with a centrifuge rotor cover is provided having a housing with a first passage, and a plunger having an annular groove and a longitudinal axis that is slidably disposed within the housing. A first biasing element is disposed within the housing. The apparatus also has an adapter having a first detent, that is removeably connected to the housing. In addition, a first moveable element is disposed within the first passage of the housing, and it is moveable between an attached position and a release position. The first moveable element is in the attached position when is within the first detent of the adapter and contacts the plunger. The apparatus also includes a first sealing element that provides a seal between the cover and rotor.
In accordance with yet a further embodiment of the present invention, an attachment and release apparatus for use with a centrifuge rotor cover is provided having a housing with a passage and a cover. It also includes a plunger having an annular groove and a longitudinal axis that is slidably disposed within the housing. A first biasing element is disposed within the housing. The apparatus also has an adapter having a detent pitched at an angle relative to the longitudinal axis, that is removeably connected to the housing. In addition, a moveable element is disposed within the passage of the housing, and it is moveable between an attached position and a release position. The moveable element is in the attached position when is at least partially in the detent of the adapter and contacts the plunger.
In accordance with yet another embodiment of the invention, a method is provided for attaching and subsequently releasing a rotor cover of a centrifuge, comprising the steps of: providing a rotor cover attachment and release apparatus having a knob with a bore extending therethrough, a cover positioned below the knob, a housing connected to the knob, a plunger disposed within the knob and housing wherein the housing has a first passage, and an adapter removeably connected to the housing, wherein the adapter has a first detent and a threaded member at its distal end; and actuating the plunger in a first direction, thereby displacing the first moveable element to contact both the plunger and the detent attaching the rotor cover to the rotor.
In yet another embodiment of the present invention, method is provided for attaching and subsequently releasing a rotor cover of a centrifuge, comprising the steps of: providing a rotor cover attachment and release apparatus having a knob with a bore extending therethrough, a cover positioned below the knob, a housing having a passage connected to the knob, an adapter having a detent, and a receiver portion connected to the housing, a plunger having a first and second contact surface slidably disposed within the bore of the knob and within the housing, a slider member disposed around the plunger that slidably engages the housing and the plunger, a first biasing member, a second biasing member, and a moveable element retained within the passage of the housing; and exerting a force in a first direction, displacing the slider member against the retaining ring, thereby displacing the moveable element between the housing and the slider member.
In accordance with another embodiment of the present invention, a method for sealing a cover to a rotor is provided, comprising: biasing a plunger having an annular groove and a longitudinal axis and disposed within a housing in a first direction; actuating the plunger in an opposite, second direction; displacing a moveable element to at partially enter the annular groove of the plunger; inserting the housing into an adapter having a detent pitched at an angle relative to the longitudinal axis; biasing the plunger in the first direction, thereby displacing the moveable element to contact the plunger and at least partially enter the detent, attaching the cover to the rotor; and rotating the housing in a third direction to urge the cover assembly to the rotor.
In this respect, before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and to the arrangements of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced and carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein, as well as the abstract, are for the purpose of description and should not be regarded as limiting.
As such, those skilled in the art will appreciate that the conception upon which this disclosure is based may readily be utilized as a basis for the designing of other structures, methods and systems for carrying out the several purposes of the present invention. It is important, therefore, that the claims be regarded as including such equivalent constructions insofar as they do not depart from the spirit and scope of the present invention.